Today it couldn’t be more clear that Russian President Vladimir Putin cannot be relied upon to keep his word, if there ever was any doubt. Friday morning last in Minsk, Putin was all smiles, hailing a new ceasefire to stop the bloodshed in Ukraine. Well, what Putin apparently meant by “ceasefire” was “now it’s time for me to unleash a major military offensive.”

Ukrainian defenders of the crucial transport hub of Debaltseve have now been overrun by the might of a Russian supplied and supported rebel army. According to the ceasefire negotiated by Germany, France, Russia and Ukraine, all fighting was to have stopped at midnight Saturday.

Putin insisted on a 60 hour delay, ostensibly to allow combatants make an orderly disengagement, but in fact to give his proxies in the so-called Donetsk People’s Republic enough time to grab a new chunk of strategically valuable territory.

But by the ceasefire deadline the Russian backed separatists still had not subdued Debaltseve. So they simply kept up their assault for another four days until the city fell. As Aleksandr Zakharchenko, the key rebel military leader bluntly put it, “the ceasefire doesn’t apply to Debaltseve.”

Time and again, Putin has shown that he does not consider Russia honor bound by mere international agreements. Russia’s annexation of Crimea last year was a violation of its 1994 agreement to respect Ukraine’s borders, its obligations under the 1975 Helsinki Accords, and the United Nations Charter.

Putin is as dishonest with the Russian public as he is with the rest of the world. According to Kremlin propaganda, Russia is defending the lives of ethnic Russians in Ukraine threatened by a fascist government in Kiev installed in a CIA led coup. And this same propaganda machine has convinced the Russian people that NATO is an imminent threat to the Motherland.

In fact, Putin himself has fomented violence and rebellion in eastern Ukraine to serve his own cynical purposes. In fact, it is the specter of Maidan that is the deadly potential danger, not to Russia, but to Putin’s kleptocratic regime. After more than two decades of post-Soviet misrule, incompetence and massive corruption, the people of Ukraine rose against and overthrew their own kleptocracy, with a resolve to build a modern European law based state and civil society.

Russia suffers from exactly the same ills of post-Soviet criminally bad governance, but with the difference the Kremlin has generous oil and gas revenues to pay for the loyalty of Putin’s acolytes and buy off domestic opposition with government spending. Now with oil prices down almost 50% the spigot is running dry, and Putin’s iron grip on power will inevitably weaken.

So Putin’s war in Ukraine is imperative to destabilize that country’s brave democratic experiment, lest it become an example for his own people. Given the stakes for Putin and his inner circle, it is no surprise that they will resort to subterfuges like clandestinely supplying arms to rag-tag rebellion they themselves created, or to casually disregarding their own signatures to international agreements.

The only logic Putin respects is power and force, whether domestically or internationally. And unfortunately, he has repeatedly shown himself to be untrustworthy. He will continue to use external aggression as a means of staying in power, unless he is met with countervailing force. The U.S. should be sending Ukraine the defensive weaponry it needs to defend its sovereignty, while at the same time serving our own interest in restraining an ambitious rogue state. It carries serious risks, but the greater risk would be to naively rely on Vladimir Putin bargaining in good faith.